Power-transmission gear for farm tractors



May 6 1924. n. c. MURNANE f Powg TRANSMISSION GEAR FOR FARM TRAcToRsFiled Nov. 50 1923 Patented May 6, 1924,

orraof srar s cORNEL'LUs NUENANE, 4or MELBOURNE, vrcronrn," AUSTRALIA.

POWER-TRANSMISSION GEAR EOE maar innerorts.

Application tiled Ncvember 30, 1923.. Serial No.i677,685.

T 0 all whom t may concer/n.:

Be it known that I, CORNELIUS MURNANE, a British subject, residing atMelbourne, Australia, have invented anWImproved Power-Transmission Gearfor Farm Tractors, of which the following is a specification. s

This invention relates to'l power transmis- 'sion gearing for farmtractors; my object being to provide farm tractors with animproved powertransmissionl gear of the friction typewhich is of a lsimple andeconomical character and adapted to be driven from eitheror both ends ofthe engine crankshaft in such a manner that said tractor. can bepropelled and steered in either direction at a high or at a low speed orbe brought to rest at will. i :l

According to my invention,fI employ a vertical engine of the reversibletype whose cylinder is provided at each sideL thereof with a fixed stubshaft extending outwardly over the ends'of the engine crankshaft, andeach of the stubV shafts carries a loosely mounted eccentric bushingupon which 'is loosely mounted a largetwo-speed vfriction wheel betweenwhose internal'and external friction faces a friction pinion fixed lon"the corresponding end of the engine .crank shaft is adapted to rotate,while each of the eccentric bushings is provided with a handlever bywhich it is free to be rocked on its stub shaft and sosimultaneously-'rock' its corresponding two-speed friction' wheel as tobring either its internal or external friction face into engagement withits corresponding friction pinion or into a neutral position relative tosaid pinion. The hubs of the two-speed friction wheels are each formedwith a sprocket wheel for transmitting the power to the final gears ofthe tractor; the arrangement being such that on bringing the internalfriction faces of the two-speed friction wheels into engagement with thefriction pinions a high speed drive in either direction is obtainable,and on bringing the external frictionfaces of the two-speed frictionwheels into engagement with the friction pinions a low speed drive ineither direction results, while on placing the two-speed friction wheelsin a neutral position relative to the friction pinions no drive will beimparted.

In order that the invention ma be clearly understood, I will proceed todyescrbe the 'comprises acrank casing Siwhose crank shaft 4 projects atvboth ends and carries the flyinsane same with reference to Jtheaccompanying wheels 5, while outside the latter and on the projectingends of the crank shaft 4 are keyed groovedvfrictio'n pinions 6. To theopposite sides of the engine cylinderA are bolted flanged stub shafts 7which extend outwardly over the projecting. endsk off-the crankshaft 4and carry loosely mounted eccentric bushings Svuponiwhich are looselymounted large wheels9 each havingv an internal groovedy friction.- face10 andan external grooved friction face A11 between which the groovedfriction pinion 6 lon the corresponding endoff'the crankshaft 4 isadapted to rotate,'while'the hubs 12 of the said Awheels 9` are formedwith sprocket" wheelsl for transmittingl the power; to thefinalgears-ofvthe tractor. Each oftheeccentric bushings 8 is providedwith a hand- 'lever14 by which'it is free'to be rocked 'on its stubyshaft 7 `into anyfone .ofthree lpositions-under the control ofj aspring-loaded @and trigger-'operated pawl 15 'carried' on saidhand-lever l4=and adapted to engage anyone of three positioning notches16 of a rack 17 fixed on the side of the engine cylinder.

When the hand-levers 14 are in the top position with their pawls 15 inengagement with the top notches 16 of the racks 17, the two-speed'friction wheels 9 are, through their bushings 8, in the positionsindicated in the drawings with their external grooved friction faces l1in engagement with their corresponding grooved friction pinions 6 on theopposite ends of the driven crank shaft 4, whereby a low speed driveofthe final gears of the tractor is obtainable in either directionaccording to the direction of rotation of the engine crank shaft 4. Onmoving the hand-levers v14 downwardly and causing their pawls 15 toengage the central notches 16 of the racks 17, the eccentric bushings 8are rocked on their stub shafts 7 so as to cause the two-speed frictionwheels 9 to be rocked into a neutral position and free their externalgrooved friction faces 11'from engagement with their correspondinggrooved friction pinions 6; while on the hand-levers 14 being furtherdepressed so as to-bring their pawls 15 into engagement with the bottomnotches 16 of the racks 17, the eccentric bushings 8 and their two-speedfriction wheels 9 are rocked` on their; stub shafts 7,

so as to bring the internal grooved friction faces 1() of the saidwheels 9 into engagement with their corresponding grooved :frictionpinions 6 on the opposite ends of lvthe driven crank shaft 4, whereby ahigh speed drive of the final gears of the tractor'is obtainable ineither direction according to the direction of rotation of the enginecrank shaft 4.

Itwill thus be seen thatby suitably'manipulating'the hand-levers 14, anyof the fricr tion faces of the two-speed friction Wheels' 9 can bebrought into engagementhwith 'their corresponding friction pinions-v(i1-either separately or -together andsocause the' tractor tobepropelled either forwardA or Vbackward and steered in. any direction;whileiby placing one hand-'lever y14 at the top position and the otherhand-lever 14: at thef bottom position, the engagement of thetwo-speed'friction wheels 9 with their corresponding friction pinions 6will be such as to `cause the sprocket wheels 13 and their final gears(not shown) to be driven in 4opposite directions yand so steer thetractor on a very short i radius.

vWhat I claim as my1invention,1and desire r `-to secure byLetters'Patent' iss- 1. Av power transmission gear of` thefriction typefor farm tractors, comprising'in combination, a vertical'reversibleengine, a stub shaftfixed 'at' each side f of :the enginecylinder extending outwardly'` over the ends l ofthe engine crank shaft,a loosely mounted eccentric bushing on each stub shaft5-a largetwo-speed friction wheel loosely'inountedl on each eccentric bushingprovided A'with rso simultaneously rock its corresponding two-speedfriction wheel .as to bring either its internal or external frictionface into engagement with its corresponding friction pinionv or into aneutral position vrelative to said pinion. i i

12. A power transmission gear of the friction type for farm tractors,comprising in combination, a vertical reversible engine, a .stub shaftfixed at each side of the engine cylinder extending outwardly, over theends yof the engine crank shaft, a loosely mountedeccentric bushing oneach stubshaft, a' large ltwo-speed grooved frictionsfaced wheel looselymounted on `each eccentric bushing provided with sprocket wheels'fortransmitting the power tothe yfinalfvgears-of the tractor, a groovedfriction-faced1pinion fixed on each end of theengine crank shaft adaptced to rotate between the internal and external grooved friction faces'ofthe correspond Aing two-speed friction wheels,y and aA hand- ;lever soneach eccentric bushing adapted to rock the latter on its stub shaft andso simultaneously rock its corresponding two-speed friction wheel as tolbring either yits internal or externaly grooved friction face into en-,gagement with its corresponding grooved .f friction-faced vpinion or'into a neutral position relative to said pinion'.

=In witness whereof I c havehereunto set `lmy'hand in the presence oftwo witnesses.

CORNELIUS MURNANE,

\ Witnesses: n

AJOHN JoWETT, .CYRIL BELLAMY.

